Outage probability of wireless-powered multi-relaying MIMO FSO-RF systems

This paper investigates a wireless-powered multi-relaying multiple-input multiple-output free space optical-radio frequency (FSO-RF) system, which consists of a source (S) with N (N≥1) laser beams, N single-antenna and single-aperture wireless-powered relaying nodes, a multi-antenna destination (D), and a single-antenna power beacon. Specifically, each beam at S is directed to the receiving aperture of a particular relay, and only one beam based on a transmit laser selection scheme is used for information transmission. Considered a nonlinear energy harvesting mode at the relays, a partial relay selection scheme based on the first hop, and a maximal ratio combining scheme at D, analytical and asymptotic expressions for outage probability are derived, which are also validated with Monte-Carlo simulations.